Hello Plumeria experts! I'm hoping you can help me salvage the branches on my plumeria.

I brought a plumeria branch back from Hawaii 3 years ago, the kind they sell at the airport. I potted it in cactus soil amended with pumice, and it's been doing OK here in San Jose, CA, living mostly indoors in a bright window, growing steadily to about twice the length it was when I got it. It finally bloomed back in October, and three branches (plus a little nub) started forming around the inflorescence. I was super excited to smell that island perfume in my house!

After flowering, the plant lost most of its leaves in December, and I figured it was going dormant as usual for winter. In February the tips of the branches started to turn black and the new leaves died. I took it outside on a sunny day, thinking that it needed some sunshine. Unfortunately, I didn't bring it back inside and the plumeria was exposed to rain and cold for several weeks (we lost a family member to causes unrelated to Covid-19, I was traveling to see them in hospice before they passed, and forgot about a lot of things).

When I finally brought it back inside, there was no improvement after a few weeks and the soil would not dry out (the enameled pot it was in had never retained so much moisture before). I decided to repot in a more breathable terracotta pot and discovered that the root ball was a lot smaller and shallower than last time I repotted, although I didn't see signs of rot. The bottom half of the stem looks good and firm, but there's a slightly soft (not spongy) section with a lesion about halfway up the stem. The branches at the top are shriveled and dark, and a little soft, but not spongy. I've attached some photos of the afflicted plant, plus some of the glorious blooms. I would greatly appreciate any advice on helping my plant recover. My specific questions are:

1. Is this black tip fungus? Can I save the branches?
2. If I cut the stem just below the middle soft spot, can I try to replant the top, or should I just cut my losses and save the bottom?
3. The soil is brand new store-bought cactus and pumice, if this is fungus do I need to repot in new soil after cutting?

Thank you in advance for your expertise!
Cheers, Kris

You might be able to make multiple cuttings from this branch. You will need a pair of sterilized pruning sheers. Cut off all areas that are soft. Healthy tissue will look white and release a milky substance. Cut until you see all healthy tissue. It looks like you might be able to make two cuttings, one from the top section and one from the rooted section. With the rooted section, it will produce new leaves and branches on its own, just leave as-is after cutting away the soft section.. The higher top section you will have to put in a separate pot and leave it for about 8 weeks so it can establish a new root system. It seems your plant can be saved, but the damaged tissue must be removed before it spreads. See attached. Good luck!

Follow the cut as mentioned above, and hope for the best. Though the shortest one you need to callus the cut ends first before you stick it into the same container or in a much smaller container with similar gritty media mix.

Yes, those rotting things happen when they get cold rain/cold temp exposure while dormant. Ideally, if it did not rain at all, your moving it outdoors was okay, but this year has been one extended rainy cold Spring, which we all need here in Cali, but not the best for the Plumies.

Position the plant in part sun/shade for now, and wait patiently for new leaves to form. NO watering till you see at least one good leaf open, leaf claws does not count. Otherwise it will just repeat the rotting process. When leaf claws are forming, you may move it to a more sunnier spot, but continue to wait patiently for the leaf to open up. Once a new leaf is fully open, then you can resume watering with intervals.

Just got to be patient, the shortest cut may or may not succeed, but you can try, if it has enough energy to do so. Good luck! My area is getting heat wave temps, don't know if the same on your side, so timing to bring it out is right now.

Thank you so much, tarev and kbrendel! This is exactly the kind of advice I needed, specifics about how/where to cut and how to get it to heal/recover. Youtube videos and website advice are all somewhat vague about cutting and how to deal with non-fungal black tip. I especially appreciate the time you took to mark up my photos, kbrendel! I will let you know what happens.

Can I ask one more question? If a light tan coloration appears on the stem, is it getting too much sun? (I never understood how wild plumeria can sit out in black lava rock in full equatorial sun in Hawaii, but my plant gets sunburned here in California, is it the humidity? Size and age of the plant?)

Thank you again!!!! -Kris

All of the above. Since your plant was indoors, it is not receiving full sun always, even the temperature is comfortably cooler than what it needs. So if you position them suddenly outside without protection, like any other plant it will get sunburnt. That is why you will often hear, do it slowly. Especially here in California, even our own gardens has such microclimates, one side may be more intense sun than on the other side.

But once the Plumie is truly fully awake with leaves, it can handle the heat and sun, provided you also give them ample watering. In their preferred growing areas, there is constant humidity, California for the most part, unless your location is more coastal, has very low humidity the further away you are from the shoreline. Our dry period is literally dry...unlike in other areas of the US they have humid, rainy summers.

I have seen them grow majestically in my homeland where it gets lots of typhoon weather in its equatorial humid heat conditions. The consistent thing there, the temperature is never below 70F and temps goes humid hot everyday, typical soil there is loam soil with volcanic origin so it is quite rich and also well draining.

Our California weather is way too different...just so many microclimates.
One thing that helps me understand my own garden is having a weather station. Though there are always daily weather news we see and hear updated, our actual gardens may register it differently. My area always meets or exceeds the forecast ...always a battle of extreme dryness and heat here once it comes around. On the flipside, it is hard to overwater my awakened Plumeria here during the dry period, water just dries out very fast. And I have made sure media is very gritty and well draining, so it will not sit in water.

Rats. I made the cuts as suggested, and while the center was whitish near the top shriveled branches, but there was no white sap, just a little clear liquid, so I cut it down further, and it gets darker and darker the further I go down. I thought the stem itself was firm, but maybe it's rotten the whole way down? Here are some pics, the white centered sections are from near the top, you can see the stem is just getting darker. Should I keep cutting, or is it a goner?

I can't really tell how tall the stem is. You may have to try to keep slicing away at it until you get to some fresh wood. I would say you would have to have at least 5"-6" of stem left for new branches to form. If you get any lower that that, your chances are going to go way down. I just had to chop up my red that had stem rot issues and black tip.

I agree with TeamCll, if it is cut way too short, there might just not be enough energy for the plant to regrow...those black rings as well is not too promising, sadly.

You may want to search for a new cutting, and start anew...or you may continue on experimenting at this stage, and see if at least one of them still manages to come back alive...though do not expect too much when it comes to blooming.